I appreciate this perspective, but I think building a tool like uv in Rust is a good idea because it's a tool for managing Python stuff, not a tool to be called from within Python code.

Having your python management tools also be written in python creates a chicken-and-egg situation. Now you have to have a working python install before you can start your python management tool, which you are presumably using because it's superior to managing python stuff any other way. Then you get a bunch of extra complex questions like, what python version and specific executable is this management tool using? Is the actual code you're running using the same or a different one? How about the dependency tree? What's managing the required python packages for the installation that the management tool is running in? How do you know that the code you're running is using its own completely independent package environment? What happens if it isn't, and there's a conflict between a package or version your app needs and what the management tool needs? How do you debug and fix it if any of this stuff isn't actually working quite how you expected?

Having the management tool be a compiled binary you can just download and use, regardless of what language it was written in, blows up all of those tricky questions. Now the tool actually does manage everything about python usage on your system and you don't have to worry about using some separate toolchain to manage the tool itself and whether that tool potentially has any conflicts with the tool you actually wanted to use.

Python is my favorite language, but I have fully embraced uv. It’s so easy, and so fast, that there is nothing else remotely close.

Need modern Python on an ancient server running with EOL’d distro that no one will touch for fear of breaking everything? uv.

Need a dependency or two for a small script, and don’t want to hassle with packaging to share it? uv.

That said, I do somewhat agree with your take on extensions. I have a side project I’ve been working on for some years, which started as pure Python. I used it as a way to teach myself Python’s slow spots, and how to work around them. Then I started writing the more intensive parts in C, and used ctypes to interface. Then I rewrote them using the Python API. I eventually wrote so much of it in C that I asked myself why I didn’t just write all of it in C, to which my answer was “because I’m not good enough at C to trust myself to not blow it up,” so now I’m slowly rewriting it in Rust, mostly to learn Rust. That was a long-winded way to say that I think if your external library functions start eclipsing the core Python code, that’s probably a sign you should write the entire thing in the other language.

> I am totally against Python tooling being written in a language other than Python

I will be out enjoying the sunshine while you are waiting for your Pylint execution to finish

>I am totally against Python tooling being written in a language other than Python. I get that C extensions exist and for the most part Python is synonymous with CPython.

>I think 2 languages are enough, we don't need a 3rd one that nobody asked for.

Enough for what? The uv users dont have to deal with that. Most ecosystems use a mix of language for tooling. It's not a detail the user of the tool has to worry about.

>I'm against it creeping into an existing eco-system for no reason.

It's much faster. Because its not written in Python.

The tooling is for the user. The language of the tooling is for the developer of the tooling. These dont need to be the same people.

The important thing is if the tool solves a real problem in the ecosystem (it does). Do people like it?

I, on the other hand, don't care what language the tools are written in.

I do get the sentiment that a user of these tools, being a Python developer could in theory contribute to them.

But, if a tool does its job, I don't care if it's not "in Python". Moreover, I imagine there is a class of problems with the Python environment setup that'd break the tool that could help you fix it if the tool itself is written in Python.

> I think 2 languages are enough, we don't need a 3rd one that nobody asked for.

Look at the number of stars ruff and uv got on github. That's a meteoric rise. So they were validated with ruff, and continued with uv, this we can call "was asked for".

> I'm against it creeping into an existing eco-system for no reason.

It's not no reason. A lot of other things have been tried. It's for big reasons: Good performance, and secondly independence from Python is a feature. When your python managing tool does not depend on Python itself, it simplifies some things.

Rust offers a feature-set that neither Python nor C has. If Rust is the right tool for the job, I would rather the code be written in Rust. Support has more to do with incentive structures than implementation language.

In theory, I can get behind what your saying, but in practice I just haven't found any package manager written in Python to be as good as uv, and I'm not even talking about speed. uv as I like it could be written in Python, but it hasn't been

What, exactly, is your objection to using rust (or any non-python/C language) for python tooling? You didn't actually give any reasons

you say "I'm against it creeping into an existing eco-system for no reason.", while you ignore that there is at least one good reason: A lot better performance.

According to the very link you provide, the sticking point was a dependency which does not use rust, and the maintainer probably being busy.

I updated a rust-implemented wheel to 3.13 compat myself and literally all that required was bumping pyo3 (which added support back in June) and adding the classifier. Afaik cryptography had no trouble either, iirc what they had to wait on was a 3.13 compatible cffi .

I'm wondering why folks aren't moving wholesale from Python to Rust, seems like it would be better for everyone.

>I am totally against Python tooling being written in a language other than Python.

Cool story bro.

I'm totally against Python tooling being in dismal dissaray for 30 years I've been using the language, and if it takes some Rust projects to improve upon it, I'm all for it.

I also not rather have the chicken-and-egg dependency issue with Python tooling written in Python.

>A popular Python package called Pendulum went over 7 months without support for 3.13. I have to imagine this is because nobody in the Python community knew enough Rust to fix it. Had the native portion of Pendulum been written in C I would have fixed it myself.

Somehow the availability and wide knowledge of C didn't make anyone bother writing a datetime management lib in C and making it as popular. It took those Pendulum Rust coders.

And you could of course use pytz or dateutil or some other, but, no, you wanted to use the Rust-Python lib.

Well, when you start the project yourself, you get to decide what language it would be in.

Upvoting for interesting/important/sympathetic perspective, but am very much in disagreement

> I'm against it creeping into an existing eco-system for no reason.

There is a reason: tools that exist today are awful and unusable if you ever wrote anything other than python.

: I'm saying it because the only way I can see someone not realizing it is that they have never seen anything better.

Okay, maybe C and C++ have even worse tooling in some areas, but python is still the top language of having the worst tooling.

I love rust but I tend to agree, python tooling should be maintainable by the community without learning a new language.

However rust is a thousand times faster than python.

At the end, if you don't like it don't use it.

I had a situation, admittedly niche, where some git based package dependency wasn't being updated properly (tags vs. commit hashes) and thanks to poetry being written in Python I was able to quickly debug and solve the problem. I think it's more a matter of core functionality (that affects everyone) vs. more esoteric or particular use cases (like dataframe libraries) that make sense to FFI.

Did you even read the issue that you pointed to? It's not even the rust part that was the issue.

Or maybe the community will embrace Rust as it is implemented... There's no reason to think because you or the current gen of Python devs are focused on C then the next gen or further will too.

I understand this sentiment. Part of it was people trying to build up their cv for Rust. On the other hand, some tools/libraries in Python were old. Take pandas for example, it was not good for modern use. We desperately needed something like polars and even that is being outpaced by current trends.